What does oil viscosity mean?
2 Answers
Oil viscosity is the most important performance indicator for measuring the fluidity of engine oil under various conditions. It mainly consists of two aspects: 1. The lower the oil viscosity, the thinner the oil film, the better the fluidity, and the relatively smaller the resistance to engine operation. 2. The higher the oil viscosity, the thicker the oil film, the weaker the fluidity, and the relatively greater the resistance to engine operation. Methods for selecting oil viscosity: 1. Based on vehicle age New cars should use oil with slightly lower viscosity, and 5W30 would be more suitable. As the vehicle ages, choose oil with slightly higher viscosity. Older car engines experience more severe wear, so relatively higher viscosity oil is needed for a more comfortable and smoother driving experience. In this case, 5W40 would be more appropriate. 2. Based on vehicle series If your car is from Europe or America and consumes too much oil, you can consider fully synthetic oil with slightly higher viscosity. Japanese and Korean cars generally have good sealing, so oil with slightly lower viscosity can be chosen, and 5W30 is a good option. 3. Based on road conditions Road conditions can greatly affect the lifespan of the oil. In areas with poor road conditions, the oil change interval should be shortened. In urban areas with frequent traffic jams and stops during driving, lower viscosity oil is recommended. If you frequently drive long distances or on highways, you can choose 5W40.
Oil viscosity, simply put, refers to how thick or thin the oil is, which affects its flow and protective performance in the engine. Different temperatures require different viscosities. In cold winter weather, oil that's too thick can make the engine hard to start and even put extra strain on the battery. In hot summer conditions, oil that's too thin may form an insufficient protective film, accelerating engine wear. You can check the SAE rating on oil labels, like 5W-30—the first number indicates cold-weather flow (smaller numbers mean better flow), while the latter number represents hot-weather viscosity (higher numbers mean thicker oil). Choosing the wrong viscosity can cause serious issues. A friend of mine used the wrong oil and ended up with increased fuel consumption and oil burning problems. It's best to refer to your vehicle's owner's manual or consult a professional mechanic rather than opting for cheaper, unsuitable products. Regular oil checks can prevent major repairs, saving both hassle and money.
